Place the given fleet of ships into the grid so that no two ships are in adjacent squares, not even diagonally. Numbers around the grid show the number of ship segments in that row or column.

As an addendum, the given fleet will usually be one 4x1 ship, two 3x1 ships, three 2x1 ships and four 1x1 ships; in some smaller grids it may be one 3x1 ship, two 2x1 ships and three 1x1 ships.

DIGITAL BATTLESHIPS: Place the given fleet of ships into the grid so that no two ships are in adjacent squares, not even diagonally. Numbers around the grid give the sum of the numbers in squares occupied by ship segments in that row or column.

I know there are a few other variants that I've seen, but I can't remember names and rules at this stage. Can someone jog my memory?

Battle Lines. The principle is the same, but numbers are in the grid, instead of around the edge of the grid. A fleet of ships is hidden in the grid. Each number in the grid tells you how many squares in the intersecting row and column contain ship parts. No two vessels lie next to each other, horizontally, vertically or diagonally. No number cell contains part of a ship.